1. Field of the Invention
The present invention generally relates to an image projector, and more particularly to architecture of generating view-dependent compensated images for a non-Lambertian surface.
2. Description of Related Art
Using an image projector in a mobile phone or digital camera greatly overcomes the screen size limitation of the handheld device and allows the image to be conveniently projected onto a bigger area on any nearby surface, such as a wall. Ideally, we would like the handheld projector to be able to project a clear image regardless of the physical characteristics of the projection surface. In practice, however, the projection surface available in the surroundings is often far from ideal and causes distortions to the projected image. As a result, compensation must be applied to the image before projection to counteract the non-ideal characteristics of the projection surface.
One fundamental assumption of most compensation techniques is that the camera is placed where the viewer is supposed to be. This assumption is easily violated since a projector-camera (procam) device can be placed at an angle with respect to the viewer. This nullifies the compensation calculated based on the assumption that the viewer and the camera are aligned or collocated at the same place. Thus, for non-Lambertian screens one should design a more general compensation algorithm that takes the viewing direction into consideration.
As a result, a need has arisen to propose a novel scheme of generating view-dependent compensated images for a non-Lambertian surface.